Back Pain and Neuraxial Anesthesia

The incidence of back pain after neuraxial anesthesia in the adult population is not different from that after general anesthesia. The pain is usually mild, localized in the low back, rarely radiates to the lower extremities, and has a duration of only a few days. The risk factors for development of back pain include the lithotomy position, multiple attempts at block placement, duration of surgery longer than 2.5 hours, body mass index ≥32 kg/m, and a history of back pain. However, there is no permanent worsening of preexisting back pain after neuraxial anesthesia. The back pain has been attributed to tears in the ligaments, fascia, or bone with localized bleeding; immobility of the spine; relaxation of the paraspinal muscles under anesthesia; flattening of the normal lumbar convexity; and stretching and straining of the lumbosacral ligaments and joint capsules. The addition of an anti-inflammatory drug to the local anesthetic used for skin infiltration may decrease the incidence and severity of back pain. The use of spinal or epidural anesthesia in the adult, non-obstetric and obstetric populations should depend on the advantages offered by the technique and not on the occurrence of back pain after the procedure. Additional studies are needed to confirm the efficacy of epidural dexamethasone, or other steroids, or the addition of an anti-inflammatory drug to the local anesthetic infiltration for the prevention of back pain after neuraxial anesthesia. Future studies should involve a physician with expertise in the evaluation of chronic low back pain to help identify the cause of the back pain and institute appropriate treatment(s).